An instant water heater (tankless heater) warms water on demand as it flows through the unit — there is no storage tank. Turn on the tap and you get hot water immediately, for as long as you need it. At Big Bath our instant heaters are compact, energy-efficient and often come with a built-in shower set, across 10 showrooms nationwide.
Why Choose an Instant Water Heater?
Never Runs Out
Because it heats on demand, there is no tank to empty — you get continuous hot water for as long as the shower runs.
Compact and Space-Saving
With no tank, an instant heater is small and mounts on the shower wall, ideal for compact bathrooms where a tank will not fit.
Energy-Efficient
It only heats water as you use it, so there is no standby heat loss from keeping a tank warm all day — lower bills for light users.
How to Choose the Right Instant Water Heater (Quick Checklist)
- Check your water pressure. Instant heaters need steady flow to trigger heating; very low pressure may need a pump or a storage tank instead.
- Built-in shower set? Many of our instant heaters come with a matched shower head and hose — one purchase, ready to fit.
- Single outlet. An instant heater usually serves one shower or basin; fit one per bathroom rather than trying to feed the whole house.
- Safety features. Look for a splash-proof body, auto cut-out and anti-scald setting.
- Use a qualified installer. It mixes water and electricity — let our team wire and plumb it safely.
Instant Water Heater Features to Look For
- Built-in shower set — matched head, hose and heater.
- Auto cut-out — shuts off on overheating or dry-fire.
- Adjustable temperature — set your preferred shower heat.
- Splash-proof (IP25) body — safe in the shower zone.
- Compact wall-mount — fits small bathrooms.
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Frequently Asked Questions
What is an instant water heater?
A tankless water heater that warms water on demand as it flows through the unit, with no storage tank. You get continuous hot water the moment you turn on the tap, for as long as you need it.
Instant or storage water heater — which is better?
An instant heater is compact, cheap to run and never runs out, but usually serves one outlet and needs steady water pressure. A storage tank heater holds a fixed volume but delivers stronger, steadier pressure and can feed several outlets. For one shower in a tight bathroom, instant is ideal.
Does an instant water heater need a pump?
Only if your water pressure is very low. The heater needs a minimum flow to switch on the heating element; if pressure is uneven, a small pressure pump fixes it. At normal Malaysian mains pressure, most instant heaters work without one.
Will an instant heater run out of hot water?
No — that is its main advantage. Because it heats on demand rather than storing a tank, you get continuous hot water for as long as the shower runs, unlike a storage tank which can empty.
Can one instant heater feed two bathrooms?
Not really. Instant heaters are sized for one outlet at a time. For two bathrooms, fit one instant heater per bathroom, or choose a storage tank / solar system sized to feed both.
Are instant heaters safe in the shower?
Our instant heaters have splash-proof (IP-rated) bodies, auto cut-out on overheating or dry-fire, and anti-scald temperature limits. They must be installed by a qualified electrician to bathroom safety standards — our team does this.
Do you deliver and install instant water heaters?
Yes. Big Bath has 10 showrooms nationwide and in-house installers across Peninsular Malaysia, with ready stock in Kota Kinabalu (Sabah) and Kuching (Sarawak). WhatsApp your nearest branch.